Light source flicker is the repetitious fading, pulsing, or flickering of a light source due to the alternating current (“AC”) frequency of the power driving the light source. Two power source frequencies predominate throughout the developed world—60 Hz (predominant in North America) and 50 Hz (predominant in Europe).
Modern imaging devices (e.g., still cameras or video cameras) often use pixel arrays (e.g., CCD arrays or CMOS arrays) to capture images. When capturing images illuminated by a flickering light source using modern pixel arrays, the rate of flickering can affect the quality of the image captured. The pixel arrays may be calibrated or tuned to compensate for one of the predominant power source frequencies. Such calibration may include synchronized image acquisition, auto-gain compensation, exposure time, or otherwise. As such, imaging devices may be designed for a particular regional market (e.g., Europe, North America) to automatically compensate for a particular power frequency (e.g., 50 Hz or 60 Hz). Some electronic devices may even include complicated and expensive circuitry to analyze the acquired image data to determine the light source power frequency. For devices that dynamically determine the light source power frequency, it is desirable to be able to detect the 50 Hz or 60 Hz power frequency in both high luminance and low luminance environments.